Capsule having a tear line

Abstract: A capsule of which cap portion 1 may be torn together with a pulling tab 6 for tearing. The capsule comprises a cap portion 1 and a skirt portion 2. Two weakening lines 4 and 5 for tearing the cap portion are provided between the cap portion 1 and the skirt portion 2. The weakening line 4 on the cap portion 1 side is inclined to a top 10 of the cap portion 1 with a certain inclination as it goes near the tear-terminating end 8. When pulling the pulling tab 6 outwardly, the cap portion 1 is torn along the weakening lines 4 and 5. Then, as getting near the tear-terminating end 8, the cap portion 1 is torn upward the top 10, thereby opening the cap portion 1. Thus, the cap portion 1 is removed from a cap of a bottle together with the pulling tab 6 in one unit.

Description: BACKGROUND ART The present invention relates to a capsule of the kind used to mount the upper parts of the neck of a bottle the mouth of which has been closed by a cork, screw-cap, bung or other form of closure, and exposed parts of the closure to provide a tamper-evidence cover for the closure, and an ornamental addition. More particularly, according to the invention, there is provided a bottle having a neck the mouth of which is closed by a bung, cork, screw-cap or other form of closure, the upper portions of the neck of the bottle and the exposed portion of the applied closure being covered by a capsule formed from a material of lead, alloy of tin and lead, tin, aluminium or any of these materials laminated with a synthetic resin film, the sides of a capsule being deformed inwardly into close contact with the surface of the neck of the bottle and any exposed laterally-facing surface of the closure, whereby the capsule is retained on the closure and provides a tamper-evidence cover for the closure. Document DE-A-2 804 851 describes a capsule according to the preamble of claim 1 comprising a tearable strip defined by two parallel tear lines which are formed by consecutive perforations. The tearable strip comprises a pulling tab which is reinforced in order to prevent a deformation during the sealing action of the bottle. In general, as illustrated in Fig. 5, a capsule comprises a cap portion 1, skirt portion 2, and a tearable guarantee strip 3 connecting the cap portion 1 and the skirt portion 2. And weakening lines 4 and 5 are provided, respectively, at a boundary between the tearable guarantee strip 3 and the cap portion 1, and at a boundary between the tearable guarantee strip 3 and the skirt portion 2. The weakening lines 4 and 5 are generally formed all over the circumference of the capsule by compressing a capsule body with a cutting knife in the direction of thickness like a perforation. A pulling tab 6 is also formed on one end of the tearable guarantee strip 3 for starting the removal by tearing. Accordingly, when pulling the tab 6 formed on the tearable guarantee strip 3 outwardly in the circumferential direction of the bottle, the tearable guarantee strip 3 is gradually torn and removed along the weakening lines 4 and 5 from the tear starting ends 7, 17 toward the tear terminating ends 8, 18 due to less strength of these lines formed compressively like a perforation. After removing completely the tearable guarantee strip 3 and the cap portion 1, the bottle is unsealed or open. A problem, however, exists in that, at the time of removing the metallic capsule by manually pulling up the cap portion 1, it is possible for fingers to feel pain or to be injured due to burr (projections with sharp edges) formed on the torn edge of the cap portion 1. This problem has been recently recognized as a result of introduction of soft tin or soft aluminum employed for a capsule material. To overcome the problem, the inventors have been aggressively engaged in various researches and developments, and already disclosed a proposal for preventing the tearable edge of the cap portion 1 and the skirt portion 2 from producing burr, as disclosed in the International Publication No. WO 93/02936. In the invention disclosed in the WO 93/02936, a variation is given to the arrangement of individual compressed parts each forming the weakening lines 4 and 5, in such a manner that burr is difficult to be produced on the tearable edges of the skirt portion 2 and the cap portion 1. The inventors have further continued the researches and developments and, as a result, it has come to an idea that if the tearable guarantee strip 3 and the cap portion 1 have been removed together in one unit without a separation from each other, it has been no more necessary to pick up only the cap portion 1 manually by fingers, eventually resulting in a prevention of fingers from feeling pain and/or being injured. DISCLOSURE OF THE INVENTION The present invention was made to solve the above-discussed problem and has an object of providing an improved capsule in which the tearable guarantee strip 3 and the cap portion 1 are removed together in one unit simply by varying the arrangement of the weakening lines without changing the manner of the compression in the individual compressed parts each forming the weakening lines. To accomplish the foregoing object, the capsule according to the invention comprises a cap portion 1 and a skirt portion 2, wherein the cap portion is separated from the skirt portion by a tearable strip defined by an upper weakening line 4 and a lower weakening line 5 and comprising a pulling tap 6, said cap portion forming one body with the tearable strip and the skirt portion being intended to remain on the bottle neck, characterized in that said tower weakening line 5 is substantially horizontal and said upper weakening line 4 is provided with an inclined part from an inclination-starting point 9a to an inclination-terminating point 9b, said inclined part satisfying an expression of [(L-Y)/X)] < 0.7 where: 0<X≤R; 0≤Y<L; "L" indicates the shortest distance from the tear-starting end 8 of the upper weakening line 4 to a top 10 of the cap portion 1; "Y" indicates the shortest distance from the tear-terminating end 8 of the upper weakening line 4 to the top 10 of the cap portion 1; "X" indicates a distance in circumferential direction from the inclination-starting point 9a of the upper weakening line 4 to the inclination-terminating point 9b thereof; and "R" indicates a circumferential length of the lower weakening line 5. There is also provided according to the invention the capsule in which the inclination-terminating point 9b of the inclined part is coincident with the tear-terminating end 8 of the weakening line 4, and the capsule in which a part of the weakening line 4 extending from the tear-starting end 7 to the inclination-starting point 9a is in parallel to the weakening line 5. There is further provided according to the invention the capsule in which a part of the weakening line 4 extending from the inclination-terminating point 9b to the tear-terminating end 8 is in parallel to the weakening line 5. As illustrated in Figure 1, the capsule according to the invention comprises a cap portion 1 for sealing a bottle, and a skirt portion 2 for sealing the upper part of a bottle neck. Thus, the portion corresponding to the conventional tearable guarantee strip 3 is solidly united with the cap portion 1 forming one body, and as a result there is substantially no independent tearable guarantee strip. The cap portion 1 and other part are formed into a shape corresponding to the cap and neck of the bottle so as to comply with a shape of the bottle, and have a hollow interior part. The cap portion 1 is a cylinder with bottom, while the skirt portion 2 is a cylinder without bottom, corresponding to the shape of the bottle which is generally cylindrical. As illustrated in Figure 1, the capsule according to the invention is provided with the weakening lines 4 and 5. The weakening line 5 is arranged in the same manner as the conventional capsule. On the other hand, the weakening line 4 is newly arranged in a manner different from the conventional capsule. The invention is characterized by this peculiar arrangement of the weakening line 4. That is, the weakening line 4 is arranged in such a manner as to meet an expression of [(L-Y)/X]<0.7 . This expression is hereinafter described with reference to Figures 2 and 3 which are both developed views of the tearable guarantee part of the capsule. In the expression, "L" indicates the shortest distance from the tear-starting end 7 of the weakening line 4 to the top 10 of the cap portion 1. Generally, "L" is a distance in the range of several mm to several tens mm. "Y" indicates the shortest distance from the tear-terminating end 8 of the weakening line 4 to the top 10 of the cap portion 1. As illustrated, the weakening line 4 is inclined toward the tearing direction and, therefore, a value of "Y" is smaller than that of "L". In this respect, there is a case of Y=0 because the tear-terminating end 8 may reach the top 10 of the cap portion 1. Accordingly, "Y" may be expressed by 0≦Y<L. "X" indicates a distance in circumferential direction from the inclination-starting point 9a of the weakening line 4 to the inclination-terminating point 9b thereof. Because the inclination-starting point 9a may be established anywhere on the weakening line 4, "X" may be expressed by 0<X≦R. There is no case of X=0 because X=0 results in Y=L which means the weakening line 4 is not inclined at all. There is a case of X=R because the inclination-starting point 9a may be coincident with the tear-starting end 7 of the weakening line 4. "X" is usually in the range of 5 to 100mm depending upon the length of "L". "R" indicates a circumferential length of a portion where the weakening line 5 is provided on the capsule. More specifically, "R" is coincident with a circumferential length of the weakening line 5. "A" indicates a distance in circumferential direction from the tear-terminating end 8 to the tear-starting end 7. Thus, A>0 in accordance with Figure 2, while A=0 in accordance with Figure 3. In both cases, the inclination-terminating point 9b is coincident with the tear-terminating end 8. After all, "X" is a distance in circumferential direction from the inclination-starting point 9a of the weakening line 4 to the tear-terminating end 8 thereof. In the invention, the weakening line 4 is not provided with any inclination satisfying an expression of [(L-Y)/X]≧0.7 by the following reason. That is, if providing such an inclination, there arises a disadvantage such that the inclined part of the weakening line 4 will be excessively inclined to the top 10 side of the cap portion 1, making it impossible to tear along the weakening lines 4 and 5. Accordingly, any portion other than the weakening lines 4 and 5 will be obliged to be torn, eventually resulting in difficulty of tearing the cap portion 1. There arises another disadvantage such that the distance in circumferential direction from the inclination-starting point 9a to the inclination-terminating point 9b will be excessively shortened, making it impossible to tear the entire cap portion 1 as a whole. Accordingly, the cap portion 1 will be obliged to be removed manually by fingers in the conventional manner. The weakening line 4 has an inclined part which inclines to the top 10 of the cap portion 1, and in which it is satisfied that the inclination-terminating point 9b or the tear-terminating end 8 is arranged so as to either reach the top 10 or extend up to several mm under the top 10. For the removal along the weakening line 4 having the inclined part together with the weakening line 5 having no inclined part, it is useful to form a guide for a tearing operation along the weakening line 4 by arranging the portion extending from the tear-starting end 7 to the inclination-starting point 9a of weakening line 4 to be in parallel to the weakening line 5, though it depends upon the steepness of the inclination. It is also useful to form a guide for terminating the tearing operation along the weakening line 4 by arranging the portion extending from the inclination-terminating point 9b to the tear-terminating end 8 of the weakening line 4 to be in parallel to the weakening line 5, as illustrated in Figure 4. The tear-terminating end 8 of the weakening line 4 may be located at any position spaced from the tear-starting end 7. Accordingly, the tear-terminating end 8 may be located either on the vertical line of the tear-starting end 7 as illustrated in Figure 3 or separately from the vertical line as illustrated in Figures 2 and 4. In addition, because the pulling tab 6 for tearing may be actually formed either with a cutout portion or with a 〈-shaped slit and, for the convenience of explanation, the tear-starting end 7 according to the invention is understood to be the one provided with such a cutout portion and located at left end. Configuration of the individual compressed parts each forming the weakening lines 4 and 5 may be freely selected from among well-known saw-tooth-like compressed parts, those formed in combination of linear compressed parts and saw-tooth-like compressed parts or perforations, circular arc compressed parts, or perforations, as disclosed in the International Publication WO 93/02936. Compressed parts formed by a conventional perforation-like configuration in combination with any of the mentioned compressed parts is also satisfied. As for the material of the capsule, tin only or tin alloy is mainly used. It is also satisfied to use aluminium only or aluminum alloy. The conventionally used lead only or lead alloy can be also employed as the material of course. It is further satisfied to use any of these materials coated with a synthetic resin film. A capsule exclusively composed of a synthetic resin (i.e., plastic capsule) is also satisfied in the invention. BRIEF DESSCRIPTION OF THE DRAWINGS Figure 1 is a front view illustrating a capsule according to an example of the present invention; Figure 2 is a developed view illustrating a tearable guarantee part of a capsule according to an example of the invention; Figure 3 is a developed view illustrating a tearable guarantee part of a capsule according to another example of the invention; Figure 4 is a developed view illustrating a tearable guarantee part of a capsule according to a further example of the invention; and Figure 5 is a front view of a capsule according to the prior art. BEST MODE FOR CARRYING OUT THE INVENTION Examples 1 to 18 and Comparative Examples 1 to 5: Capsules each having weakening lines 4 and 5 as illustrated in Figures 2 and 3 were prepared by using a tin foil of 300 µm in thickness as illustrated in Figure 1. A depth of individual compressed parts each forming the weakening lines 4 and 5 was set to be 0.2mm, and in which values of the mentioned reference symbols "R", "L", "Y", "X", etc. are as indicated in Table 1. The capsules of above construction were then subjected to a test for determining whether or not the cap portion thereof was simultaneously removed together with the pulling tab for unsealing or opening the capsules. Three-grade evaluation was adopted by marking with "○", "X", and "▵". That is, "○" indicates an evaluation of a capsule which was smoothly unsealed such that the cap portion was simultaneously removed together with the pulling tab. "X" indicates an evalution of a capsule of which the cap portion was not removed together with the pulling tab. This was because a tearing direction got out of the weakening line of the inclined part due to an excessively large inclination. "▵" indicates an evaluation of a capsule in which the mentioned evaluations "○" and "X" were found almost evenly. Table 1 shows the results. R (mm) L (mm) Y (mm) L-Y (mm) A (mm) X (mm) (L-Y)/X Evaluation Examples 1 100 6 0 6 0 95 0.063 ○ 2 100 6 5 1 0 95 0.011 ○ 3 100 6 0 6 0 80 0.075 ○ 4 100 6 2 4 0 80 0.500 ○ 5 100 8 0 8 0 80 0.100 ○ 6 100 8 2 6 0 9 0.667 ○ 7 100 10 2 8 0 20 0.400 ○ 8 100 10 2 8 0 25 0.320 ○ 9 100 10 2 8 0 50 0.160 ○ 10 100 10 5 5 0 60 0.083 ○ 11 100 10 5 5 0 75 0.067 ○ 12 100 10 5 5 0 80 0.063 ○ 13 100 10 0 10 0 100 0.100 ○ 14 100 10 2 8 0 100 0.080 ○ 15 100 10 5 5 0 100 0.050 ○ 16 100 8 1 7 13 57 0.123 ○ 17 100 10 3 7 13 57 0.123 ○ 18 100 10 4 6 5 70 0.086 ○ Comparative Examples 1 100 6 2 4 0 5 0.800 X 2 100 10 2 8 0 10 0.800 X 3 100 10 0 10 0 10 1.000 X 4 100 10 3 7 0 10 0.700 ▵ 5 100 10 1 9 5 10 0.900 X Examples 19 to 22 and Comparative Examples 6 to 7: The same capsules as the Examples 1 to 18, except that they were provided with the weakening lines 4 and 5 as illustrated in Figure 4, were prepared and performances thereof were evaluated in the same manner as the Examples 1 to 18. Table 2 shows the results. In Table 2, the tear starting parallel portion indicates a length (mm) of a part being in parallel to the weakening line 5 extending from the tear-starting end 7 to the tear-inclination-starting point 9a, and the tear-terminating parallel portion indicates a length (mm) of a part being in parallel to the weakening line 5 extending from the inclination-terminating point 9b to the tear-terminating end 8. R (mm) Tear starting parallel portion L mm Y mm L-Y (mm) X mm (L-Y)/X Tear terminating parallel portion A mm Evalution Examples 19 100 15 10 4 6 70 0.086 5 5 ○ 20 100 15 10 5 5 70 0.071 5 5 ○ 21 100 15 8 2 6 70 0.086 5 5 ○ 22 100 15 8 2 6 75 0.080 5 0 ○ Comparative Examples 6 100 80 10 2 8 10 0.800 5 5 X 7 100 15 12 2 10 10 1.000 75 0 X It is understood from Tables 1 and 2 that, in the capsules of Examples 1 to 22, the pulling tab and the cap portion were simultaneously removed together in one unit. On the other hand, in the capsules of Comparative Examples, the pulling tab and the cap portion were not torn along the weakening line 4 due to the excessively large inclination, but torn at a portion out of the weakening line, thus making it difficult to tear the cap portion. As has been described so far, in the capsule of above construction and arrangement according to the invention, the weakening line 4 on the cap portion 1 side comes to have a specific inclination as it goes near the tear-terminating end 8, thereby forming an inclined part toward the top 10. Accordingly, when pulling the pulling tab 6 outwardly, the cap portion 1 is torn first along the weakening line 4, and then as getting near the tear-terminating end 8, the cap poriton 1 is torn upwardly to the top 10 of the cap portion 1. Thus, the cylindrical cap portion comes to be open without a separation of the pulling tab 6 and the cap portion 1 during the tearing operation, and after completing the tearing operation, the cap portion 1 can be easily removed upward from the cap of the bottle together with the pulling tab 6. In other words, it is not necessary to touch the cap portion 1 since the cap portion 1 can be removed just by pulling the pulling tab 6 with fingers, and therefore there is no more disadvantage that fingers touch the burr formed on the torn edge of the cap portion 1. As a result, a remarkable advantages is exhibited such that there is substantially no possibility of feeling pain in fingers or injuring any finger at the time of unsealing a bottle. Another peculiar advantage is such that since the cap portion 1 is torn together with the pulling tab 6 in one unit (i.e., there is no conventional tearable guarantee strip), there is no more problem of tearing off the tearable guarantee strip on the midway of unsealing operation.

Claims: A capsule comprising a cap portion (1) and a skirt portion (2), wherein the cap portion is separated from the skirt portion by a tearable strip defined by an upper weakening line (4) and a lower weakening line (5) and comprising a pulling tab (6), said cap portion forming one body with the tearable strip and the skirt portion being intended to remain on the bottle neck, charakterized in that, said lower weakening line (5) is substantially horizontal and said upper weakening line (4) is provided with an in clined part from an inclination-starting point (9a) to an inclination-terminating point (9b), said inclined part satisfying an expression of [(L-Y)/X)) < 0.7 where: 0<X≤R; 0≤Y<L; "L" indicates the shortest distance from the tear-starting end (7) of the upper weakening line (4) to a top (10) of the cap portion (1); "Y" indicates the shortest distance from the tear-terminating end (8) of the upper weakening line (4) to the top (10) of the cap portion (1); "X" indicates a distance in circumferential direction from the inclination-starting point (9a) of the upper weakening line (4) to the inclination-terminating point (9b) thereof; and "R" indicates a circumferential length of the lower weakening line (5). A capsule as set forth in claim 1, wherein said inclination-terminating point (9b) is coincident with said tear-terminating end (8). A capsule as set forth in claim 1 or 2, wherein a part of said upper weakening line (4) extending from said tear-starting end (7) to said inclination-starting point (9a) is in parallel to said lower weakening line (5). A capsule as set forth in claim 1 or 3, wherein a part of the upper weakening line (4) extending from said inclination-terminating point (9b) to said tear-terminating end (8) is in parallel to said lower weakening line (5).

Inventors: EGUCHI TATSUO, TAMURA YOSHITAKA, UEDA TOSHIHIRO, EGUCHI, TATSUO, TAMURA, YOSHITAKA, UEDA, TOSHIHIRO, EGUCHI, TATSUO, C/O SHIGA-FACTORY, TAMURA, YOSHITAKA, C/O SHIGA-FACTORY
Applicants: NIPPON FOIL MFG, SUNTORY LTD, NIPPON FOIL MFG CO., LTD., SUNTORY LIMITED
Application year: 1994
Main classification: B65D41
IPC codes: B65D41, B65D51